Replace ARGSUSED comment-based annotation with GCC 'unused' attribute.

Turn on unused-parameter checking for GCC.

* alloc.c (GC_try_to_collect_general): Add GC_ATTR_UNUSED attribute
to an argument.
* tests/test.c (tiny_reverse_test, thr_run_one_test): Likewise.
* backgraph.c (reset_back_edge, update_max_height): Replace ARGSUSED
annotation with GC_ATTR_UNUSED attribute for some arguments.
* checksums.c (GC_add_block): Likewise.
* dbg_mlc.c (GC_debug_change_stubborn, GC_debug_end_stubborn_change,
GC_check_heap_block): Likewise.
* finalize.c (GC_null_finalize_mark_proc): Likewise.
* gcj_mlc.c (GC_gcj_fake_mark_proc): Likewise.
* mark.c (GC_noop, clear_marks_for_block, GC_mark_and_push): Likewise.
* mark_rts.c (GC_push_conditional_with_exclusions,
GC_push_current_stack): Likewise.
* misc.c (GC_default_oom_fn, GC_do_blocking_inner): Likewise.
* os_dep.c (GC_fault_handler_openbsd, GC_fault_handler,
GC_remove_protection, GC_page_was_dirty, GC_page_was_ever_dirty):
Likewise.
* pthread_stop_world.c (GC_suspend_handler, GC_suspend_handler_inner):
Likewise.
* pthread_support.c (GC_do_blocking_inner): Likewise.
* stubborn.c (GC_change_stubborn, GC_end_stubborn_change): Likewise.
* tests/test.c (fail_proc1): Likewise.
* typd_mlc.c (GC_array_mark_proc): Likewise.
* win32_threads.c (GC_do_blocking_inner, DllMain): Likewise.
* include/private/gc_priv.h (GC_ATTR_UNUSED): Define new macro.
* cordxtra.c (CORD_ATTR_UNUSED): Likewise.
* cordxtra.c (CORD_nul_func, CORD_lf_close_proc): Replace ARGSUSED
annotation with CORD_ATTR_UNUSED attribute for an argument.
* mach_dep.c (GC_clear_stack_inner): Remove ARGSUSED annotation and
use "limit" argument in the function (to suppress compiler warning).
* misc.c (GC_clear_stack_inner): Remove ARGSUSED.
* tests/threadkey_test.c (on_thread_exit_inner, on_thread_exit):
Use all function arguments (to suppress compiler warning).
* configure.ac (CFLAGS): Remove "-Wno-unused-parameter" option.

1 files changed, 16 insertions, 10 deletions

diff --git a/cord/cordxtra.c b/cord/cordxtra.c
index 5904d3b2..abb34f64 100644
--- a/cord/cordxtra.c
+++ b/cord/cordxtra.c
@@ -21,19 +21,21 @@
 # include <string.h>
 # include <stdlib.h>
 # include <stdarg.h>
+
 # include "cord.h"
 # include "ec.h"
+
 # define I_HIDE_POINTERS    /* So we get access to allocation lock. */
                 /* We use this for lazy file reading,   */
-                /* so that we remain independent    */
-                /* of the threads primitives.       */
+                /* so that we remain independent        */
+                /* of the threads primitives.           */
 # include "gc.h"
 
 /* For now we assume that pointer reads and writes are atomic,  */
 /* i.e. another thread always sees the state before or after    */
-/* a write.  This might be false on a Motorola M68K with    */
+/* a write.  This might be false on a Motorola M68K with        */
 /* pointers that are not 32-bit aligned.  But there probably    */
-/* aren't too many threads packages running on those.       */
+/* aren't too many threads packages running on those.           */
 # define ATOMIC_WRITE(x,y) (x) = (y)
 # define ATOMIC_READ(x) (*(x))
 
@@ -45,8 +47,8 @@
 #   define SEEK_END 2
 # endif
 
-# define BUFSZ 2048 /* Size of stack allocated buffers when     */
-            /* we want large buffers.           */
+# define BUFSZ 2048     /* Size of stack allocated buffers when */
+                        /* we want large buffers.               */
 
 typedef void (* oom_fn)(void);
 
@@ -54,6 +56,12 @@ typedef void (* oom_fn)(void);
               ABORT("Out of memory\n"); }
 # define ABORT(msg) { fprintf(stderr, "%s\n", msg); abort(); }
 
+#if __GNUC__ >= 4
+# define CORD_ATTR_UNUSED __attribute__((__unused__))
+#else
+# define CORD_ATTR_UNUSED /* empty */
+#endif
+
 CORD CORD_cat_char(CORD x, char c)
 {
     register char * string;
@@ -425,8 +433,7 @@ void CORD_ec_append_cord(CORD_ec x, CORD s)
     x[0].ec_cord = CORD_cat(x[0].ec_cord, s);
 }
 
-/*ARGSUSED*/
-char CORD_nul_func(size_t i, void * client_data)
+char CORD_nul_func(size_t i CORD_ATTR_UNUSED, void * client_data)
 {
     return((char)(unsigned long)client_data);
 }
@@ -551,8 +558,7 @@ char CORD_lf_func(size_t i, void * client_data)
     return(cl -> data[MOD_LINE_SZ(i)]);
 }
 
-/*ARGSUSED*/
-void CORD_lf_close_proc(void * obj, void * client_data)
+void CORD_lf_close_proc(void * obj, void * client_data CORD_ATTR_UNUSED)
 {
     if (fclose(((lf_state *)obj) -> lf_file) != 0) {
         ABORT("CORD_lf_close_proc: fclose failed");